Collapsin Response Mediator Proteins (CRMPs) are a family of phosphoproteins that may mediate semaphorin/collapsin-induced growth cone collapse and are involved in axonal guidance and neuronal differentiation. See, for example, Goshima et al. (1995) Nature 376: 509-14; Fukada et al. (2000) J Biol Chem. 275: 37957-65; Minturn et al. (1995) J Neurosci 15: 6757-66; Wang & Stittmatter (1996) J NeruoSci 16: 6197-207; Byk et al. (1996) J Neurosci 16: 688-701; and Gaetano et al. (1997) J Biol Chem 272: 12195-201.
Five members (CRMP-1, CRMP-2, CRMP-3, CRMP-4, and CRMP-5) of the CRMP family related to 60-66 kDa proteins have been independently cloned by several different laboratories pursuing different goals. One characterized function of proteins of the CRMP family is the repulsive guidance of nerve axons. The functional role of the CRMPs in this process has been studied (Quinn et al. (1999) J Neurobiol 41: 158-64). The CRMPs have about 50%-70% amino acid sequence homology among the five family members (Hamajima et al. (1996) Gene 180: 157-63), and they have been proposed to form heterotetramers through mutual associations (Wang & Stittmatter (1997) J Neurochem 69: 2261-9). However, each of the CRMPs displays a distinct expression pattern during development in the nervous system and in response to nerve growth factor induction of neuronal differentiation (Byk et al. (1998) Eur J Biochem 254: 14-24).
CRMP-2 was found associated with neruofibrillary tangles in Alzheimer's patients (Gu et al. (2000) Biochemistry 39: 4267-75). CRMP-3 and CRMP-5 were recognized by autoantibodies in patients of small cell lung cancers with paraneoplastic neurological syndrome (Yu et al. (2001) Ann Neurol 49: 146-54; and Honnorat et al. (1999) Eur J Neurosci 11: 4226-32).